NYC property research library
Research NYC property records with the source boundaries intact.
Practical guides for navigating permits, violations, complaints, occupancy records, recorded documents, and the identifiers that connect them. Each guide links to official sources, carries a review date, and explains what a public-record search cannot establish.
Start with the property
3 guidesNYC property due-diligence checklist
An interactive and print-friendly workflow for property identity, DOB, HPD, occupancy, ACRIS, zoning, and public context.
Read guide →NYC property due diligence: a public-record research workflow
A practical, evidence-first workflow for researching NYC permits, violations, complaints, ownership records, and source coverage.
Read guide →BBL vs. BIN: the NYC property identifiers researchers should not mix up
A plain-language explanation of NYC borough-block-lot and building identification numbers, including condos and multi-building lots.
Read guide →Buildings, permits, and occupancy
5 guidesDOB NOW vs. BIS: where to search NYC building records
A practical comparison of DOB NOW and BIS, including which NYC permits, filings, violations, complaints, and occupancy records each system contains.
Read guide →How to research NYC DOB permits and job filings
A guide to DOB NOW and legacy BIS permit data, job filings, dates, identifiers, and common interpretation mistakes.
Read guide →How to find and read an NYC Certificate of Occupancy
Where to find NYC Certificates of Occupancy in DOB NOW and BIS, what floor-use records show, and what a missing or temporary certificate means.
Read guide →How to research NYC building violations
How DOB, OATH/ECB, and HPD violation records differ, how to read status fields, and what a records search cannot prove.
Read guide →How to research NYC HPD complaints and violations
How HPD complaints, problems, inspections, and housing-maintenance violations relate—and where their limits matter.
Read guide →Ownership and public context
2 guidesHow to search ACRIS for NYC property records
A practical workflow for finding NYC deeds, mortgages, and other recorded documents in ACRIS without treating the index as a title conclusion.
Read guide →What NYC 311 service requests can—and cannot—tell you about a property
How to use NYC 311 service-request data as dated public context without turning complaints into unsupported conclusions.
Read guide →What these guides can—and cannot—do
These pages support public-record research. Records may be stale, incomplete, duplicated, ambiguous, or temporarily unavailable. Missing records do not prove compliance, safety, legal occupancy, title condition, or that an event never occurred. Verify material items with the responsible agency and qualified professionals.
Put the records into one reviewable workspace
LotContext organizes supported NYC public records by property identity, source, status, and retrieval time. It is research support, not a title report, inspection, or legal opinion.
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